Antenna mount and coaxial conductor connection thereto



J. F. ULRICH March 3, 1964 ANTENNA MOUNT AND COAXIAL CONDUCTOR CONNECTION THERETO Filed Oct. 30, 1962 Arron/v5 KW/ o United States Patent 3,123,665 ANTENNA MOUNT AND COAXIAL CONDUCTOR CONNECTION THERETO James F. Ulrich, Brecksville, Ohio, assignor to The Tenna Mfg. Co., Inc, Warrensville Heights, Ohio, a corporation of Puerto Rico Filed Oct. 30, 1962, Ser. No. 234,087 1 Claim. (Cl. 174-153) This invention relates to radio antenna mounts and more particularly to such devices used in two-way short wave radio communication between ambulant and/or non-ambulant stations, as, for instance, for installation in the roof of an automobile.

An object of the invention is to provide an antenna mount of this class which is easy to install in and remove from the roof of a vehicle from the outside.

Another object is a construction having no loose parts below the mounting surface such as the roof of a vehicle.

A further object of my invention is to provide a mount which, after installation, is characterized by extreme rigidity and which will not become loosened as a result of vibration and long use.

A further object of the invention is to provide a mount of the type defined which is waterproof both as to moisture leakage through and around the mount and into the interior of the vehicle through the mounting opening.

A still further object is a mount having integral means for gripping an end of a coaxial cable.

Still another object is to provide a base and post section having means engageable with and adapted to spread or bind the end of an inner stranded conductor or to bind a single conductor to the engaging means to provide effective electrical contact between the post and the conductor at the end of the conductor and at the same time alford a positive anchorage between the end of the conductor and the contacting end of the post.

Another object is to insure an eifective mechanical and electrical connection for the woven shielding conductor with the stem portion of the mount.

Another object is to provide an intenna post which is threaded at its inner end for self threading engagement with a surrounding insulation sleeve.

Other objects and advantages of my invention will become more apparent as the following description of an embodiment thereof progresses, reference being made to the accompanying drawing in which like reference numerals are employed to designate like parts throughout the same.

In the drawings:

FIGURE 1 is a side elevation illustrating an embodiment of my invention in which the mount assembly is shown distended with its principal elements arranged in order of assembly. This view also illustrates in broken lines the manner of inserting the lead-in cable and the base and post from the outside of the mounting surface, such as an auto roof panel;

FIGURE 2 is a vertical central mount and mounting panel; and

FIGURE 3 is a section taken in the direction indicated by the line 33 of FIGURE 2.

In carrying out my invention, an embodiment of which is illustrated in the drawings, the mounting support, such as a roof panel of an automobile, is indicated at 1, and is drilled to provide an opening 2 of minimal size through which the lead-in cable 3 and mounting base 4 is inserted from the top of the mounting surface, as shown in broken lines in BIGURE 1.

The mounting base comprises a body having oppositely disposed bosses 5 and 6 of equal or unequal length, as desired, both of which have relatively wide flat surfaces 7 section through the having area contact With the underside of the support 1. Locating bosses are formed integral with the upper surface of the base as indicated at 8 and are provided for the purpose of properly locating the base within the opening '2 in assembling the mount in the panel 1. In the drawing I have shown the locating boss overlying the upper flat surface of the longer boss 5 as of greater length than that portion of the boss 8 which overlies the upper flat surface of the shorter boss 6. The locating bosses 8 are diametrically opposed and serve as positioning means to properly align and maintain the lugs 5 and 6 in gripping position with the under surface of the panel 1. When the base is located in the opening 2 in the panel, as shown in broken lines in FIGURE 1, by inserting first the longer boss 5 through the opening 2 while the base is tilted, and then inserting the shorter boss 6, it will be noted that by then bringing the base to upright position, as shown in full lines, and then shifting it slightly to the right, the bosses 5 and 6 will underlie the under surface of the support 1 with their fiat surfaces 7 bearing against the said under surface. In such position, when the mount is fully assembled, the same will be rigidly secured to the panel 1, as will be explained more fully hereinafter.

Although I have shown the bosses 5 and 6 as being of unequal length, it is to be understood that the invention contemplates the use of bosses such as 5 and 6 which are not necessarily of unequal length.

As indicated in broken lines in FIGURE 1, with the associated parts shown as removed fromthe base in FIGURE 1, it will be seen that the base may be shifted to the left so that the shorter boss 6 will be free of contact with the under surface of the support 1, thereby permitting the base and stem assembly to be tilted as shown, and removed through the minimal opening 2 along with the cable 3.

The base carries an integral threaded stem portion, indicated at 9, which extends upwardly from the base and is threaded upwardly from the base, as at 10. The stem is of generally cylindrical form and has a bore extending therethrough into which an insulating sleeve 11 is fitted to extend throughout the length of the post and into the base. Included in the stem assembly is a metallic rod or post 12 pointed at its lower end into substantially conical form, as indicated at 13, and is provided With threads 14 for a short distance above the pointed end portion 13. The upper end of the rod 12 terminates in an enlarged headed portion '15. The insulating sleeve 11 extends upwardly from within the base 4 and surrounds the rod 12 up to the headed portion 15, as shown clearly in FIGURE 2.

The post head 15 is provided with an axial opening 16 for receiving the end of the antenna rod 17 which is secured therein by means of a set screw 18. The free end of the antenna rod may terminate in a sphere or the like 19.

It will be seen that as the rod 12 is threaded into the insulating sleeve to the position shown in FIIG'URE 2, the pointed or conical end of the rod, as at 13, will be driven into the cluster of strands of the inner electrical conductor 12' and will spread and bind them against the insulation 11 to provide a good contact between the strands and the rod 1-2, or if the center conductor 12' is in the form of a single conductor, it will be bound against the rod 12 to provide good electrical contact therewith. At the same time, the shield covering 20 of the conductor which has its exposed ends inserted between the lower end of the insulating sleeve 11 and the base 4 will be bound against the lower end of the insulating sleeve and thereby grounded against the inner surface of the base bore carrying the sleeve.

Integral with the base and preferably the longer boss 5, I provide a pair of bendable cable gripping fingers 21 which are adapted to embrace the shield or the outer covering of the end of the cable which is connected with the base and which, when contracted thereabout, will firmly grip the same and maintain it in clamped position so that the shield covering 2th will remain gripped beween the insulation '11 and the base 4 or by the lingers 21, and the conductor housed within the insulating cover 22 will [remain in good electrical contact with the rod 12. Both the conductor and the shielding cover will be effectively bound in the base by this means, but will be insulated from each other.

The installation of the mount in an opening of minimal size in a roof top is extremely simple by virtue of the construction of the mount. After the hole 2 is drilled in the roof or support 1, and it is freed on burrs or other obstructions, the cable 3 is first fed through the opening from the top and since one of its ends is already assembled in the base and stem as it is drawn through the opening 2 the base 4- is inserted into the opening by first passing the longer boss 5 down through the opening, as indicated in broken lines in FIGURE 1, and while the base and stem assembly are in tilted position. sembly is then brought to a vertical position so that the shorter boss can be passed down through the opening 2, and while the bosses 5 and 6 are below the under surface of the support 1, the assembly is shifted in a direction away from the direction of the cable 3, that is, to the right in FIGURE 1, until the upper surface of the shorter boss 6 lies flat against the under surface of the support ll. At the same time, the upper surface of the longer boss 5 will lie flat against the under surface of the support 1 on the opposite side of the opening 2. Flats 23 are provided on opposite sides of the stem to be engaged by a wrench or manually while finally tightening the mounting nut 27. With the assembly firmly held in this position, and after the fiat 'lfitfii washer 24 and mounting nut 27 internally threaded as at 28, are brought down over the stem to engage the threads in of the stem, and the nut is turned to bring it down past the hats 2,3 and against the washer and the support :l, the nut can then be finally tightened while holding the stem asembly against movement relative to the panel 1 and the opening 2. When the mounting nut is securely tightened, the base and stem assembly will be firmly secured in the panel 1. 'Ihe set screw 18 may be loosened and the antenna rod '17 removed from the head d5. The sealing washer 25 is then assembled over the unit and in the position, as shown in FIGURE 2, to lie against the upper surface of the support, and then the dress nut 3t? which is internally threaded at 31 is threaded onto the threads 29' of the mounting nut and its lower portion is brought into sealing engagement with the rubber washer 25.

In assembling the antenna rod 17 in the mount, it is first trimmed to a predetermined length suitable for the frequency used and after it is trimmed, its lower end is inserted in the opening 16 and the head and the rod is then secured in place by tightening the set screw 18. The selected length of the antenna rod for the frequency used is readily determined by consulting charts which are available for this purpose.

This as- It will be seen from the above that the assembly is rendered moisture proof by the engagement of the dress nut with the sealing Washer 25 which exerts sufiicient pressure on the washer to sealingly engage the same with the upper surface of the support 1. To seal against moisture entering the interior of the assembly, an O-ring 32 is provided in a groove in the upper portion of the dress nut to sealingly engage the insulation sleeve 11.

Various changes may be made in the details of construction and arrangement of parts of the invention without departing from the spirit thereof or the scope of the appended claim.

I claim:

An antenna structure adapted to be inserted from above and to be secured in a minimal opening in a panel and which comprises a base having integral oppositely disposed mounting lugs formed on the base and having flat surfaces disposed to engage the under surface of the panel, a hollow externally threaded stem integral with the base to extend above the panel, an insulating sleeve telescoped within the stem and extending beyond the upper end of the stem, said sleeve having a radially extending portion engageable with the upper end of the stem to limit its lowermost position in the stem, an insulated coaxial conductor comprising an outer shield conductor and an inner conductor insulated from the shield and proiecting into the base, said conductors coextending upwardly into the stem and terminating within the confines of the sleeve, conductor clarnping means integral with one of said lugs and disposed below the base for clamping an end portion of the coaxial conductor to one of said lugs, the terminal ends of the inner and outer conductors respectively extending upwardly and within the insulating sleeve and between the sleeve and the inner wall of the hollow stern and base, an antenna post mounted in the sleeve and having wedging means projecting into binding engagement with the terminal end of th inner conductor to expand the same and the adjacent end of the sleeve to exert a binding pressure on the said end of the inner conductor, the sleeve, and the said end of the outer conductor and against the inner wall of the stem whereby to establish electrical contact between the inner conductor and the antenna post and to establish a ground contact between the outer conductor and the stem and base, and a mounting nut threaded on the stem to draw the base and integral mounting lugs into clamping engagement with the panel area adjacent the minimal mounting opening therein.

References Cited in the file of this patent 

